Knife cutter

ABSTRACT

A knife cutter having a rotary rod-like knife and a flexible bowed stationary knife which is engaged and flexed upon rotation of the rotary knife to enhance the shearing effect for cutting record media, such as paper, spooled off a roll and to cause the knives to continuously sharpen themselves. The bowed and flexibility of the stationary knife has the additional advantage of making the positioning of the knives less critical which, together with means of easy removal of the knives from their cutting position facilitates maintenance thereof.

Unite States atent n91 Waihel 4] KNIFE CUTTER Helmut K. Waibel, San Leandro, Calif.

[73] Assignee: The Singer Company, New York,

[22] Filed: Mar. 19, 1973 [21] Appl. No.: 342,642

[75] Inventor:

[52] US. Cl 83/602, 83/174, 83/542, 83/583, 83/611, 83/694 [51] int. C1 18236.1 17/00, B23d 15/10 [58] Field of Search 83/174, 542, 583, 611, 83/610, 602, 612, 694

[56] References Cited UNITED STATES PATENTS 1,005,879 10/1911 Ries 83/611 X 3,512,439

5/1970 Kallenberg et a1 83/611 X June 4, 1974 3,568,556 3/1971 Gesell 83/611 X Primary Examiner-J. M. Meister Attorney, Agent, or Firm-Edward L. Bell; Joseph R.

Dwyer [5 7] ABSTRACT 4 Claims, 7 Drawing Figures BACKGROUND OF THE INVENTION 1. Field of Invention This invention relates, in general, to knife cutters for cutting record media, and in particular, to the cutting of paper spooled off a roll, and in particular to point-ofsale type data terminals having a spool of paper on which sales transactions are printed and which are cut by the instant invention for the purposes of providing a customer receipt.

2. Description of the Prior Art Knife cutters for cutting media rolled off a spool have been used in postal meters, as best described and claimed in U.S. Pat. No. 3,062,133 to I. H. Lundguist et al., which issued on Nov. 6, 1962.

In that patent, the knife cutter shown comprised a rotary cutter rod and a stationary knife blade which cut the paper transversely upon rotation of the rod. The rotary rod had a flat surface which formed the cutting edge and, as the rod was rotated with the paper therebetween, the cutting edge engaged the cutting edge of the stationary blade for the shearing effect.

The knife cutter, as disclosed in the patent, and as actually made, however, had maintenance problems. The positioning of the blade edges relative to each other was critical for proper shearing and it was difficult to align the two even though a guide means was provided. Too, guide means was difficult to disassemble when it was necessary to remove the stationary blade for sharpening and it.was similarly difficult to reassemble and align. This made this device difficult and expensive to maintain.

Even though the knife cutter worked extremely satisfactory in the postal meter, where the paper being cut was about one and one-half inches, the difficulty in aligning the knife edges made it impractical to cut wider paper of approximately three and one-fourth to three and one-half inches in width.

In this invention, as described and claimed herein, the stationary knife and the rotary rod-like knife to provide the shearing effect is again used, but in this invention the stationary knife is bowed and flexible, being bowed and flexed toward the rotary knife. This flexure and bend, which yields to the rotation of the rotary knife, provides the enhanced shearing effect, makes the two blades self-sharpening and also renders the positioning of the blades to one another in the guide means less critical. Thus, with the self-sharpening aspect, the simplified mounting reduces the maintenance problems and provides a much better knife cutter for both narrow and wide paper.

SUMMARY OF THE INVENTION A knife cutter having a rotary knife and a stationary knife, together with actuating means for rotating the rotary knife. The stationary knife is flexible and bowed toward the rotary knife, which is flexed by rotation of the cutting knife to enhance the shearing effect and to cause the knives to continually sharpen each other. The assembly is also provided with a simple guide means for positioning the stationary knife, and the rotary knife is pivotally mounted for access to both the stationary and rotary knives.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective of a cutaway portion of a data terminal schematized to illustrate the relationship of the customer receipt station in which the cutting device forming the present invention is incorporated and its co-operation with the rest of the data terminal, including the matrix printer which prints on the receipt to be cut for presentation to the customer;

FIG. 2 is a side view of the knife cutter illustrating the position of the rotary knife blade in cutting position and also in phantom, illustrating the position for access to the stationary knife;

FIG. 3 is also a side view of the knife cutter, but looking in the opposite direction of FIG. 2;

FIG. 4 is an elevational cross-sectional view of the knife cutter taken along the line 4-4 of FIG. I and looking in a direction of the arrows;

FIG. 5 is an elevational cross-sectional view taken along the line 55 of FIG. 1 and looking in a direction of the arrow, but additionally showing the rotary knife pivoted away from the stationary knife and further showing the manner in which the'stationary knife can be easily removed from its position for maintenance purposes;

invention- DESCRIPTION OF Tl-IE PREFERRED EMBODIMENT To illustrate a data terminal, in which the present invention may be used, a general description thereof is described first.

In FIG. 1, the data terminal 10 (with cover removed for purposes of clarity) is shown as comprising, overall, a carriage l2 movable laterally with respect to a frame 14, a platen 16 having three print stations 18, 20 and 22, and an appropriate keyboard 24. The three print stations 18, 20 and 22 are, respectively, a receipt station where the customers receipt is printed (if a receipt is required), an audit station where the storekeepers record (audit trail) of all transactions are printed, and a form station where the customer's order form or bill of sale is printed, if required.

By this arrangement, the carriage 12 will move, not only from the printing position shown, viz, at the audit station and receipt station, but to the form station and audit station as well as traversing each pairs of stations so that appropriaterows and columns of. data entered into the data terminal at the keyboard 24 is appropriately printed out. The carriage 12 is mounted on a pair of bars 26 and 28 to hold the carriage in parallel relationship with the platen l6 and the rest of the data terminal and traverse movement on the parallel bars is accomplished by a suitable drive mechanism 30 including a belt 12 attached to carriage I2, and pulley means 34 motivated by a reversible motor (not shown).

In the embodiment shown, a receipt 16, if required, is printed in the receipt station 18 and an audit trail 38 is printed in the audit station 20 when the carriage 12 is in the position shown as the two record media (paper) are moved forward, i.e., in the direction of the keyboard 24, and forms a suitable supply, such as a roll of paper, by a suitable roller feed mechanism driven by a motor and clutch means 42 coupled to shaft 44. When the carriage 12 is positioned to the left from that shown, a form 46, such as customer order form or bill of sale, is printed in station '22 at the same time the audit trail 38 is being printed.

The audit trail 38 is rolled onto a spool 48 partially shown in FIG. 11, while the receipt 36 is severed, when a complete transaction is recorded, by a suitable cutting mechanism, indicated in its entirety as 49'. Also, the forms station is provided with a pair of electronic sensing means 5(1) and 52 which determine when a form 46 is properly located in the forms station, otherwise the terminal is inhibited from operating; suitable electronics being provided for this purpose. Rollers 54 feed the form in a direction opposite from the direction of travel of the audit trail by suitable gearing to couple the rollers to shaft 42 which moves the form and audit trail or audit trail and receipt, or audit trail alone, as the I case may be incrementally, in response to and in combination with the printing mechanisms to form rows and columns of data as determined by the input to the keyboard 24.

The carriage 12 is also provided with a pair of matrix printers 56 and 58 capable of printing on two of the three stations at the same time, viz, the receipt station and the audit station, or when the carriage is positioned to the left from that shown in the form station and audit station.

For the proper positioning of the rows and columns of the characters on the record media, the combination of a mechanical strobe means 60 and suitable electronics cooperating therewith are provided but are described and claimed in a copending application in more detail.

Furthermore, a suitable ink supply means for the dual matrix printer located in the carriage are shown in FIG.

i. only schematically, since the ribbon, its novel inking supply arrangement and other details to improve the operation of the matrix printers and data terminals generally are described and claimed in a copending application.

No description of such mechanical strobe means and electronics for properly aligning the characters on the record media nor in the ink supply means for the printers will be described herein since this invention is directed to the knife cutter for cutting a customer receipt at the receipt station which will now be described in more detail.

It should be noted at this time, however, that the matrix printers in cooperation with suitale electronics described and claimed in the copending applications, supra, print on the receipt upside down relative to the printing on the audit trail and form. This upside down printing on the receipt enables the complete transaction, such as a sale, to be recorded and totaled in the manner in which any transaction is normally read, i.e., top to bottom, for the benefit of the customerv This is also true of the form printed at the form station since the form moves in a direction opposite to the direction of travel of the receipt. This is not true, however, for the printing on the audit trail, which is stored in the machine to be used by the vendor.

Turning now to FIGS. 2, 3 and 41, it can be seen that the knife cutter is identified in its entirety as 62 and includes a rod-like rotary knife 64 and a stationary knife 66, both mounted in a pair of side plates 68 and '70.

Each of the side plates are provided with an opening in which the knife blades operate and end walls 72 (one shown in FIG. 2) form a stop or shoulder against which the stationary knife rests when inserted in notches 74 (one shown in FIG. 2). Shoulders 72 and notches 74 serve as a guide to precisely locate the stationary knife in the knife cutter. The rotary knife, on the other hand, is mounted on a pair of pivot arms 76, 78 which pivots about a shaft 80 mounted in the side plates; the pivot arms being provided with bearing surfaces in the form of notches 82 (one shown in FIG. 2) opening toward the stationary knife as shown in FIG. 2. These bearing surfaces support the rotary knife for rotation therein.

In FIG. 3, it can be seen that there is also provided a linkage in the form of link arm 84 and lever 86 pivotally connected at 88. Lever 86 is fixed to the rotary knife and serves to rotate the knife upon actuation of the link arm 84.

In order to provide a cutting edge on the rotary knife, the central portion of the rod is machined or cut away as at 88, providing a flat surface extending axially the length of the rod except, of course, near the ends which provide the bearing surfaces for rotation in bearing surfaces 82. The flat portion thus provides a precise cutting edge 90 on the rotary knife which effects a shearing action upon actuation by engagement with the cutting edge 92 on the stationary blade formed by the tapered surface 94.

Turning now again to FIG. 4, it can be seen that the linkage for rotating the rotary knife is actuated by any suitable means, such as cams or solenoids, cam 96 being shown, which engages a cam follower 98 mounted on a bail assembly 100. The bail assembly comprises two cam arms I02 and 104 joined in the center 106 so as to loop over a shaft 108 which rotates therewith. The ball assembly is biased in one direction by a returnspring 110, the position shown in FIG. 4, which is attached at one end B04 and at the other end to the side plate 70. Thus, actuation by the cam 96 serves to move the bail assembly against the operation of the bias spring 110, causing movement of a second cam follower 112 engaged by arm 104 in a clearance slot 118, said cam follower being mounted on the link 84 (FIG. 3) and fixed to the arm 104 by rivet 129. At the appropriate time, upon further rotation of the cam 96, the bias spring will cause the bail assembly to return to its original position, such as shown in FIG. 4.

Thus, in operation, paper, such as that shown at 34 in FIG. I spooled from a roll (not shown) is fed through a pair of guides E22 and 124 by a pair of spring-biased feed rollers 126 and 128 beneath the flat edge 88 of the rotary knife when the latter is in a position shown in FIG. 4. Operation of the cam 96 at the appropriate time, as sensed by a signal entered into the keyboard 24, will move cam follower 96 upeardly, causing actuation of the bail assembly and the linkage 84, 86 to rotate the rotary knife in a direction as indicated in FIGS. 4 and 7, with knife edges 90 and 92 severing the paper transversely thereat. After such cutting and upon further movement of the cam 96, the bias spring will return the rotary knife to a position shown in FIG. 4, permitting the next portion of the paper to pass across the knife by the operation of the feed rollers.

Having just described the operation of the device, the self-sharpening feature, and the automatic selfalignment and ease of maintaining the cutting device will now be described.

To accomplish the self-sharpening feature, attention is directed to FIGS. 6 and 7 and again to FIG. 1.

ln P16. 6, the stationary knife 66 is shown bowed and flexed in the direction of the rotary knife. Also, in FIG. 1 shown greatly exaggerated as at 127, is the slope on the cutaway surface 88 which forms a slightly sloped surface of about from one end of the rod to the other, defining a slope to the cutting edge 90 so that upon rotation of the rotary knife, this cuttingedge engages the bow in the stationary knife; the latter yielding, engaging this edge so as to continually be urged against the cutting edge of the rotary knife, yet flexing upon influence of the cutting edge, thus causing a continually sharpening action as well as a shearing action on the material being cut.

Now, as to the facility for maintenance of the cutter, the automatic alignment of the stationary knife is a combination of the bow in the knife, the simplicity of the guide means 72 and 74, plus the ease in access to the stationary knife and rotary knife. As shown in FIGS. 2and 4, the rotary knife 66 can be pivoted away from the stationary knife by the pivot arms 76, 78 by the simple removal of the fastening means 130, which, as shown, is a hexagonal rod 132 and nut disposed through holes in the pivot arms 76, 78 and side plates 68, 70. The pivoting of the rotary blade away from the stationary knife enables the stationary knife to be removed from the notches 74 as shown in H6. 5 and replaced in the guide means 72, 74 and the rotary knife brought into position again as shown in H05. 3 and 4 and fixed by the fastening means 130. The holes in the pivot arms 76, 78 for the fastening means 130 are slightly larger than the rods 132 to enable slight adjustment of rotary knife 64 rotating to the stationary knife before the nut is tightened. Too, if it is desired to remove and replace the rotary blade, it can be easily done when the pivot arms are in position for removal of the stationary knife. I

From the foregoing it can be seen that there is disclosed a knife cutter which provides an enhanced shearing effect and has the additional advantage of providing for automatic positioning as well as selfsharpening, which accomplishes the ease of maintenance as aforesaid mentioned. The self-sharpening feature has been found to work extremely well in practical application. As a matter of fact, after positioning, the self-sharpening feature allows the cutter to break in," requiring less torque to rotate the rotary knife without loss of cutting ability.

While this invention has been described in connection with a data terminal in which it finds extreme usefulness, obviously this invention could be used wherever a knife cutter of the type disclosed is used.

What is claimed is:

ll. A knife cutter for shearing record media such as paper and including means for feeding such media through said cutter comprising:

a rotary knife provided with a cutting edge;

a stationary knife provided with a cutting edge;

said stationary knife being flexible and bowed toward the rotary knife and engageable therewith and subject to being flexed upon rotation of the rotary knife to perform a shearing operation on the record media located between said knives;

means for mounting said stationary knife and said rotary knife in shearing engagement with one another; and

means for actuating said rotary knife.

2. The knife cutter as claimed in claim 1 wherein said rotary knife cutting edge is slightly skewed to enhance its shearing action.

3. The knife cutter as claimed in claim 1 wherein said mounting means comprises guide means for positioning the stationary knife and pivotal arms for positioning the rotary knife in shearing engagement with the stationary knife.

4. The knife cutter as claimed in claim ll wherein said actuating means comprises camming means and linkage means, the latter being attached to the rotary knife and movable upon actuation of the camming means to rotate the rotary knife. 

1. A knife cutter for shearing record media such as paper and including means for feeding such media through said cutter comprising: a rotary knife provided with a cutting edge; a stationary knife provided with a cutting edge; said stationary knife being flexible and bowed toward the rotary knife and engageable therewith and subject to being flexed upon rotation of the rotary knife to perform a shearing operation on the record media located between said knives; means for mounting said stationary knife and said rotary knife in shearing engagement with one another; and means for actuating said rotary knife.
 2. The knife cutter as claimed in claim 1 wherein said rotary knife cutting edge is slightly skewed to enhance its shearing action.
 3. The knife cutter as claimed in claim 1 wherein said mounting means comprises guide means for positioning the stationary knife and pivotal arms for positioning the rotary knife in shearing engagement with the stationary knife.
 4. The knife cutter as claimed in claim 1 wherein said actuating means comprises camming means and linkage means, the latter being attached to the rotary knife and movable upon actuation of the camming means to rotate the rotary knife. 